I am investigating about a problem with overflow entries in 2D histograms. In some 2D histograms produced in my analysis with Athena, the total number of events doesn’t match the number of entries +U/Overflows.
I have understood that actually that the overflows were not an integer but the number of overflows/#bins(in the proper coordinate). On the other hand the overflows at the bin-coordinates (0,0), (0,NYbin+1) (NXbin+1,0), (NXbin+1,NYbin+1) where generally wrong.
I tried an example of my own by filling a 2D histogram and then checking the u/overflows and this worked fine. This means that is not a general problem.
All times I accessed the bins with “GetBinContent” method and the Root version is 04.02.00 (but I think that is still the same for the latest release).
Is this problem related to the way these histograms are filled (inside Athena ?) . Is there some other method to read the u/overflows in 2D histograms ? Does anyone have seen something similar ?
Many thanks for your attention.